The present invention relates to a disposable diaper of a type requiring no diaper cover and more particularly to such diaper provided in areas surrounding respective thighs and/or waist with leakage preventing means containing elastic flaps.
The U.K. Patent Disclosure Gazette No. 2,181,336A discloses garments such as disposable diapers, which are provided with leakage preventing means comprising elastic flaps for fitting around the respective thighs of the wearer. The leakage preventing means disclosed therein comprises first flaps extending outwardly and provided with respective elastic members, and second flaps each having one side edge provided with an elastic member and the opposite side edge connected to a main body of the article wherein said one side edge is collapsed inwardly and, in this condition, subjected to fixation at longitudinally opposite ends thereof.
Each of said second flaps is provided to form a pocket adapted to block transverse flow of any excretions as this second flap is allowed to be raised under the contractile force of the elastic member associated therewith. With an article having such construction, said pockets are opened around the thighs of the wearer with said second flaps being raised under the contractile force of the respective elastic members against the crotch area (an area defined between both thighs) Simultaneously, said first flaps have been folded on the inner sides of the article and pressed against the respective thighs under the effect of the associated elastic members. In such a situation, the folding lines of said first flaps are in coincidence with base lines of the corresponding second flaps, i.e., the lines along which said second flaps are connected to the main body of the article, and said second flaps are not pressed against the thighs.
It should be noted here that the degree to which each of said pockets is opened depends upon the angle at which the corresponding second flap is raised. For example, when the wearer takes a posture with the thighs largely outstretched so as to stretch said second flaps, or when the wearer sits down with said second flaps inwardly collapsed, said pockets are insufficiently opened so that the desired blocking effect of said pockets against excretions, particularly such as loose feces and urine, can not be obtained and this inconveniently results in leakage thereof.
A primary object of the present invention is to resolve the problem as above mentioned and to provide a leakage preventing means for disposable diapers that is adapted to achieve a sealing effect sufficiently high to block leakage of excretions.
The present invention is directed to disposable diaper comprising a liquid-permeable topsheet, a liquid-impermeable backsheet, an absorbent core sandwiched between both sheets, and a leakage preventing means subjected to the effect of elastic members.
Said leakage preventing means comprises flexible flaps and elastic members, said flaps each including a support portion extending upwardly from the main body of the diaper, an inner branched portion extending inwardly from said support portion, an outer branched portion extending outwardly from said support portion and said elastic member being disposed in association with both said inner and outer branched portions so as to form elastic gathers in these portions.
It is most preferable to dispose a pair of such leakage preventing means, for use around the legs of the wearer, along opposite sides of said absorbent core longitudinally thereof so that the inner branched portions are usually pressed under the effect of the elastic members against the respective thighs rather than the crotch area, and the pockets formed at least by respective inner surfaces of said inner branched portions and the associated support portions are maintained in their adequately opened positions independently of the posture taken by the wearer. As a consequence, said pockets can effectively block leakage of excretions, particularly of loose faces and urine. Simultaneously, said inner branched portions cooperate with said outer branched portions to achieve the high sealing effect necessary to block leakage of excretions, since said outer branched portions located adjacent said inner branched portions are also elastically pressed against the respective thighs.
Said leakage preventing means may also be disposed along the waist line of diaper, if desired, to achieve the same good sealing effect.
Stated differently, the present invention concerns a disposable diaper having a front, a back and lateral sides and further including a liquid permeable topsheet, a liquid impermeable backsheet, and absorbent core sandwiched between these sheets, and excrement leakage preventing means in the form of flexible flaps located outwardly with respect to the absorbent core. Each flexible flap comprises a support portion extending upwardly with respect to the surface of the diaper. An inner branched portion, an entire length of which extends inwardly from an upper part of the support portion, is generally parallel to the backsheet. An outer branch portion, the entire length of which extends outwardly from the upper part of the support portion, is also generally parallel to the backsheet. At least one elastic member is incorporated into both the inner and outer branch portions to form elastic gathers in these two portions. A pocket is formed by an inner surface of a support portion and the inner branch portion which serves to impede the leakage of excretions from the diaper.
The diaper inner branched portion includes an upper segment which extends inwardly from an upper part of the support portion parallel to the backsheet and a lower segment extending outwardly towards the support portion generally parallel to the backsheet.
In another aspect, the outer branched portion includes an upper segment extending outwardly from an upper part of tie support portion generally parallel to the backsheet and a lower segment extendingly inwardly toward the support portion generally parallel to the backsheet.
Preferably, at least one elastic member extends parallel to the backsheet.
Preferably, the inner branched portion has a width greater than a thickness thereof. Likewise, the outer branch portion preferably has a width greater than the thickness thereof.
In accordance with the further feature, the support portion, the inner branch and the outer branch portion are together formed from the same strip of material that is doubled onto itself to form the portions. The at least one elastic member extends a full width of both the inner and outer branch portions.
The width of at least one of the inner and outer branch portions is approximately equal to a height of the support portion in a preferred embodiment.
The invention also concerns a disposable diaper having a front, a back and lateral sides and further includes a liquid permeable topsheet, a liquid impermeable backsheet, and an absorbent core sandwiched between the sheets and excrement leakage preventing means in the form of flexible flaps located outwardly with respect to the absorbent core. The flexible flap comprising a support portion extending upwardly with respect to the surface of the diaper. An inner branch portion, having a width which extends about one half a distance between the support portion and an outer most longitudinal edge of the core and extending from an upper part of the support portion, is generally parallel to the backsheet. An outer branch portion extends outwardly from the support portion generally parallel to the backsheet. At least one elastic member is incorporated into both of the inner and outer branch portions to form elastic gathers in these two portions. A pocket is formed by an inner surface of the support portion and the inner branch portion which serves to impede the leakage of excretions from the diaper.
In a preferred embodiment of this invention, each inner branch and outer branch portion is elongate and has a top surface which is flat. Each branch portion can be bent upwardly and downwardly from the upper end of the support from which they project so that each branch is independently deformable to closely contact a wearer""s skin. For this purpose, the length and flexibility of each branch, particularly the inner branch portion, must be adequate in the direction from which it extends from the support portion. In the preferred embodiment, each branch has a length in the direction of the absorbent core which is at least three times as large as the thickness of the associated support.
In the preferred embodiment, the opposite longitudinal ends of each of the inner and outer branch portions are preferably fixed to the topsheet which advantageously assures that the pocket is opened and stabilized in the position depicted in FIG. 2. In a variation of the preferred embodiment, it is preferred that at least the opposite ends of the inner branch portion be fixed in their longitudinally stretched condition to ensure close contact with a wearer""s skin by virtue of the elongation stress of the elastic member contained in the branch.
In the preferred embodiment, the flexible flap is formed with a T-shape in cross-section as defined by the support portion and the inner and outer branch portions which ensures a more stable contact with a wearer""s skin as compared with a flap, for example, in the form of an L-shape.
The support portion, the inner branch portion and the outer branch portion are together formed from the same strip of material that is doubled onto itself to form the portions. At least one elastic member extends the full width of both inner and outer branch portions. Preferably, a width of at least one of the inner and outer branch portions is approximately equal to a height of the support portion. Also preferably, the inner branch portion includes a width greater than a thickness and the outer branch portion also includes a width greater than a thickness.
In accordance with another aspect of the invention, a disposable diaper has a back and lateral sides and further includes a liquid permeable topsheet, a liquid impermeable backsheet and absorptive core sandwiched between the sheets, and excrement leakage preventing means in the form of at least one flexible flap located outwardly with respect to the absorbent core. The at least one flexible flap comprises a support portion extending upwardly with respect to a surface of the diaper. This support portion supports a outer branch portion which extends outwardly from an upper part of the support portion and an inner branch portion which extends inwardly from the upper part of the support portion. At least one elastic member is incorporated into both the inner and outer branch portions to form elastic gathers into these two portions. Both the inner and outer branch, portions are fixed to a body of the diaper at longitudinal ends thereof and under longitudinally stretched conditions of the elastic member so that the inner branch portions and at least a top part of the supporting portion extend upwardly of a top surface of a top sheet and above an area defined by a top surface of the core with the inner branch portion spaced away from the top surface of the topsheet under the elastically contractible force of the elastic member. A pocket is jointly formed by the top sheet covering a side edge of the core, the support portion and the inner branch portion. The pocket is thereby maintained in an open position independently of a wearer""s posture to impede the leakage of excretions from the diaper.